Multi-mode power management system supporting fifth-generation new radio

ABSTRACT

Embodiments of the disclosure relate to a multi-mode power management system supporting fifth-generation new radio (5G-NR). The multi-mode power management system includes first tracker circuitry and second tracker circuitry each capable of supplying an envelope tracking (ET) modulated or an average power tracking (APT) modulated voltage. In examples discussed herein, the first tracker circuitry and the second tracker circuitry have been configured to support third-generation (3G) and fourth-generation (4G) power amplifier circuits in various 3G/4G operation modes. The multi-mode power management system is adapted to further support a 5G-NR power amplifier circuit(s) in various 5G-NR operation modes based on the existing first tracker circuitry and/or the existing second tracker circuitry. In this regard, the 5G-NR power amplifier circuit(s) can be incorporated into the existing multi-mode power management system with minimum hardware changes, thus enabling 5G-NR support without significantly increasing component count, cost, and footprint of the multi-mode power management system.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 62/489,727, filed on Apr. 25, 2017, which isincorporated herein by reference in its entirety.

FIELD OF THE DISCLOSURE

The technology of the disclosure relates generally to radio frequency(RF) power amplifier circuits.

BACKGROUND

Mobile communication devices have become increasingly common in currentsociety for providing wireless communication services. The prevalence ofthese mobile communication devices is driven in part by the manyfunctions that are now enabled on such devices. Increased processingcapabilities in such devices means that mobile communication deviceshave evolved from being pure communication tools into sophisticatedmobile multimedia centers that enable enhanced user experiences.

A fifth-generation (5G) new radio (NR) (5G-NR) wireless communicationsystem has been widely regarded as the next wireless communicationstandard beyond the current third-generation (3G) communicationstandard, such as wideband code division multiple access (WCDMA), andfourth-generation (4G) communication standard, such as long-termevolution (LTE). The 5G-NR wireless communication system is expected toprovide a significantly higher data rate, improved coverage range,enhanced signaling efficiency, and reduced latency compared to wirelesscommunication systems based on the 3G and 4G communication standards.Moreover, the 5G-NR communication system is an orthogonal frequencydivision multiplexing (OFDM) based wireless system designed to operateacross a wide range of radio frequency (RF) bands, which include alow-band (below 1 GHz), a mid-band (1 GHz to 6 GHz), and a high-band(above 24 GHz).

A portion of the 5G-NR RF bands, particularly the low-band and themid-band, overlaps with the RF bands currently used by the 3G and/or the4G wireless communication systems. As such, the 5G-NR wirelesscommunication system is designed to provide greater scalability acrossall the 5G-NR RF bands. For example, the 5G-NR wireless communicationsystem can scale down to operate in the 3G/4G RF bands based on the3G/4G wireless communication standard for lower throughput applicationsand/or in suburban locations, and scale up to operate in the 5G-NR RFbands based on the 5G-NR communication standard for higher throughputapplications and/or in urban/indoor locations. As such, it may bedesired for the 3G, 4G, and 5G-NR communication standards to coexist inthe mobile communication devices.

SUMMARY

Embodiments of the disclosure relate to a multi-mode power managementsystem supporting fifth-generation new radio (5G-NR). The multi-modepower management system includes first tracker circuitry and secondtracker circuitry each capable of supplying an envelope tracking (ET)modulated or an average power tracking (APT) modulated voltage. Inexamples discussed herein, the first tracker circuitry and the secondtracker circuitry have been configured to support third-generation (3G)and fourth-generation (4G) power amplifier circuits in various 3G/4Goperation modes. The multi-mode power management system is adapted tofurther support a 5G-NR power amplifier circuit(s) in various 5G-NRoperation modes (e.g., 5G-NR high power mode and 5G-NR low power mode)based on the existing first tracker circuitry and/or the existing secondtracker circuitry. In this regard, the 5G-NR power amplifier circuit(s)can be incorporated into the existing multi-mode power management systemwith minimum hardware changes, thus enabling 5G-NR support withoutsignificantly increasing component count, cost, and footprint of themulti-mode power management system.

In one aspect, a multi-mode power management system is provided. Themulti-mode power management system includes a power amplifier circuitconfigured to amplify a 5G-NR signal to an output power level fortransmission in a 5G-NR band. The power amplifier circuit includes acarrier amplifier configured to amplify the 5G-NR signal to a firstpower level in response to receiving a first bias voltage at a firstbias voltage input. The power amplifier circuit also includes a peakingamplifier configured to amplify the 5G-NR signal to a second power levelin response to receiving a second bias voltage at a second bias voltageinput. A sum of the first power level and the second power level equalsthe output power level. The multi-mode power management system alsoincludes first tracker circuitry configured to generate a first voltageat a first voltage output. The multi-mode power management system alsoincludes second tracker circuitry configured to generate a secondvoltage at a second voltage output. The multi-mode power managementsystem also includes control circuitry. The control circuitry isconfigured to couple the first voltage output to the first bias voltageinput and the second bias voltage input in a 5G-NR low power mode. Thecontrol circuitry is also configured to couple the first voltage outputand the second voltage output to the first bias voltage input and thesecond bias voltage input, respectively, in a 5G-NR high power mode.

In another aspect, a multi-mode power management system is provided. Themulti-mode power management system includes a power amplifier circuitconfigured to amplify a signal to an output power level. The poweramplifier circuit includes a carrier amplifier configured to amplify thesignal to a first power level in response to receiving a first biasvoltage at a first bias voltage input. The power amplifier circuit alsoincludes a peaking amplifier configured to amplify the signal to asecond power level in response to receiving a second bias voltage at asecond bias voltage input. A sum of the first power level and the secondpower level equals the output power level. The multi-mode powermanagement system also includes first tracker circuitry configured togenerate a first voltage at a first voltage output. The multi-mode powermanagement system also includes second tracker circuitry configured togenerate a second voltage at a second voltage output. The multi-modepower management system also includes control circuitry. The controlcircuitry is configured to couple the first voltage output to the firstbias voltage input and the second bias voltage input in a low powermode. The control circuitry is also configured to couple the firstvoltage output and the second voltage output to the first bias voltageinput and the second bias voltage input, respectively, in a high powermode.

Those skilled in the art will appreciate the scope of the presentdisclosure and realize additional aspects thereof after reading thefollowing detailed description of the preferred embodiments inassociation with the accompanying drawing figures.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The accompanying drawing figures incorporated in and forming a part ofthis specification illustrate several aspects of the disclosure and,together with the description, serve to explain the principles of thedisclosure.

FIG. 1A is a schematic diagram of an exemplary conventional Dohertypower amplifier circuit;

FIG. 1B is a graph providing exemplary illustrations of signalsgenerated in the conventional Doherty power amplifier circuit of FIG.1A;

FIG. 2A is a schematic diagram of an exemplary existing multi-mode powermanagement system that can be adapted to support variousfifth-generation new radio (5G-NR) operation modes;

FIG. 2B is a schematic diagram of an exemplary serial power amplifiercircuit that can be provided in the existing multi-mode power managementsystem of FIG. 2A for amplifying second-generation (2G),third-generation (3G), and/or fourth-generation (4G) signals;

FIG. 3 is a schematic diagram of an exemplary multi-mode powermanagement system, which is adapted from the existing multi-mode powermanagement system of FIG. 2A, for supporting various fifth-generationnew radio (5G-NR) operation modes;

FIG. 4 is a schematic diagram of an exemplary reconfigurable loadmodulation power amplifier circuit that may be provided in themulti-mode power management system of FIG. 3 for supporting the various5G-NR operations; and

FIG. 5 is a schematic diagram of an exemplary multi-mode powermanagement system incorporating the reconfigurable load modulation poweramplifier circuit of FIG. 4.

DETAILED DESCRIPTION

The embodiments set forth below represent the necessary information toenable those skilled in the art to practice the embodiments andillustrate the best mode of practicing the embodiments. Upon reading thefollowing description in light of the accompanying drawing figures,those skilled in the art will understand the concepts of the disclosureand will recognize applications of these concepts not particularlyaddressed herein. It should be understood that these concepts andapplications fall within the scope of the disclosure and theaccompanying claims.

It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, these elements should notbe limited by these terms. These terms are only used to distinguish oneelement from another. For example, a first element could be termed asecond element, and, similarly, a second element could be termed a firstelement, without departing from the scope of the present disclosure. Asused herein, the term “and/or” includes any and all combinations of oneor more of the associated listed items.

It will be understood that when an element such as a layer, region, orsubstrate is referred to as being “on” or extending “onto” anotherelement, it can be directly on or extend directly onto the other elementor intervening elements may also be present. In contrast, when anelement is referred to as being “directly on” or extending “directlyonto” another element, there are no intervening elements present.Likewise, it will be understood that when an element such as a layer,region, or substrate is referred to as being “over” or extending “over”another element, it can be directly over or extend directly over theother element or intervening elements may also be present. In contrast,when an element is referred to as being “directly over” or extending“directly over” another element, there are no intervening elementspresent. It will also be understood that when an element is referred toas being “connected” or “coupled” to another element, it can be directlyconnected or coupled to the other element or intervening elements may bepresent. In contrast, when an element is referred to as being “directlyconnected” or “directly coupled” to another element, there are nointervening elements present.

Relative terms such as “below” or “above” or “upper” or “lower” or“horizontal” or “vertical” may be used herein to describe a relationshipof one element, layer, or region to another element, layer, or region asillustrated in the Figures. It will be understood that these terms andthose discussed above are intended to encompass different orientationsof the device in addition to the orientation depicted in the Figures.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the disclosure.As used herein, the singular forms “a,” “an,” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises,”“comprising,” “includes,” and/or “including” when used herein specifythe presence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure belongs. It willbe further understood that terms used herein should be interpreted ashaving a meaning that is consistent with their meaning in the context ofthis specification and the relevant art and will not be interpreted inan idealized or overly formal sense unless expressly so defined herein.

Embodiments of the disclosure relate to a multi-mode power managementsystem supporting fifth-generation new radio (5G-NR). The multi-modepower management system includes first tracker circuitry and secondtracker circuitry each capable of supplying an envelope tracking (ET)modulated or an average power tracking (APT) modulated voltage. Inexamples discussed herein, the first tracker circuitry and the secondtracker circuitry have been configured to support third-generation (3G)and fourth-generation (4G) power amplifier circuits in various 3G/4Goperation modes. The multi-mode power management system is adapted tofurther support a 5G-NR power amplifier circuit(s) in various 5G-NRoperation modes (e.g., 5G-NR high power mode and 5G-NR low power mode)based on the existing first tracker circuitry and/or the existing secondtracker circuitry. In this regard, the 5G-NR power amplifier circuit(s)can be incorporated into the existing multi-mode power management systemwith minimum hardware changes, thus enabling 5G-NR support withoutsignificantly increasing component count, cost, and footprint of themulti-mode power management system.

In a non-limiting example, the 5G-NR power amplifier circuit(s) can beconfigured to function according to the functional principles of aDoherty power amplifier circuit. As such, before discussing exemplaryaspects of a multi-mode power management system supporting a 5G-NR poweramplifier circuit(s) in various 5G-NR operation modes, a brief overviewof a conventional Doherty power amplifier circuit is first provided withreference to FIGS. 1A and 1B. A discussion of an existing multi-modepower management system already supporting various 3G and 4G operationmodes, which can be adapted to support various 5G-NR operations modes isthen provided with references to FIGS. 2A and 2B. The discussion ofspecific exemplary aspects of a multi-mode power management systemsupporting a 5G-NR power amplifier circuit(s) in various 5G-NR operationmodes starts below with reference to FIG. 3.

FIG. 1A is a schematic diagram of an exemplary conventional Dohertypower amplifier circuit 10. The most essential elements of theconventional Doherty power amplifier circuit 10 include a splitter 12, acarrier amplifier 14, a peaking amplifier 16, and a combiner 18. Thesplitter 12 receives an input signal 20 and splits the input signal 20into a first signal 22 and a second signal 24. The first signal 22 has afirst phase θ₁. The second signal 24 has a second phase θ₂, which is aninety-degree (90°) offset from the first phase θ₁.

The carrier amplifier 14 is configured to amplify the first signal 22 upto a first peak power P₁ in response to receiving a first bias voltageV₁ at a first bias voltage input 26. The first peak power P₁ is themaximum power level the carrier amplifier 14 can linearly produce beforereaching a respective compression point and losing linearity.

The peaking amplifier 16 is configured to amplify the second signal 24up to a second peak power P₂ in response to receiving a second biasvoltage V₂ at a second bias voltage input 28. The peak power P₂ is themaximum power level the peaking amplifier 16 can linearly produce beforereaching a respective compression point and losing linearity.

The combiner 18 is configured to combine the first signal 22 and thesecond signal 24 to generate an output signal 30, which has a peak powerthat equals P₁+P₂. In this regard, the second peak power P₂ may beconsidered a “top-up” power to the first peak power P₁, as is furtherillustrated below in FIG. 1B.

In this regard, FIG. 1B is a graph 32 providing exemplary illustrationsof the first signal 22, the second signal 24, and the output signal 30generated in the conventional Doherty power amplifier circuit 10 of FIG.1A. As shown in FIG. 1B, the first signal 22 has a first peak power P₁,the second signal 24 has the second peak power P₂, and the output signal30 has the peak power P₁+P₂.

FIG. 2A is a schematic diagram of an exemplary existing multi-mode powermanagement system 34 that can be adapted to support various 5G-NRoperation modes. The existing multi-mode power management system 34includes a low-band (LB) power amplifier circuit 36, a first mid-band(MB) power amplifier circuit 38, a first high-band (HB) power amplifiercircuit 40, an ultra-high-band (UHB) power amplifier circuit 42, asecond MB power amplifier circuit 44, a second HB power amplifiercircuit 46, a second-generation (2G) LB power amplifier circuit 48, anda 2G HB power amplifier circuit 50.

In a non-limiting example, the LB power amplifier circuit 36 isconfigured to amplifier a 3G signal, such as a wideband code divisionmultiple access (WCDMA) signal, and/or a 4G signal, such as a long-termevolution (LTE) signal, for transmission in a 450-960 MHz band. As such,the LB power amplifier circuit 36 may be configured to function as aWCDMA LB power amplifier circuit or an LTE LB power amplifier circuit.

Each of the first MB power amplifier circuit 38 and the second MB poweramplifier circuit 44 is configured to amplify the 3G signal and/or the4G signal for transmission in a 1710-2200 MHz band. Accordingly, each ofthe first MB power amplifier circuit 38 and the second MB poweramplifier circuit 44 is configured to function as a WCDMA MB poweramplifier circuit and/or an LTE MB power amplifier circuit.

Each of the first HB power amplifier circuit 40 and the second HB poweramplifier circuit 46 is configured to amplify the 3G signal and/or the4G signal for transmission in a 2300-2700 MHz band. Accordingly, each ofthe first HB power amplifier circuit 40 and the second HB poweramplifier circuit 46 is configured to function as a WCDMA HB poweramplifier circuit and/or an LTE HB power amplifier circuit.

The UHB power amplifier circuit 42 is configured to amplifier the 3Gsignal and/or the 4G signal for transmission in a 3400-3800 MHz band. Assuch, the UHB power amplifier circuit 42 may be configured to functionas a WCDMA UHB power amplifier circuit or an LTE UHB power amplifiercircuit.

The 2G LB power amplifier circuit 48 is configured to amplifier a 2Gsignal, such as a WCDMA signal, and/or a 4G signal, such as globalsystem for mobile communication (GSM) and enhanced data rates for GSMevolution (EDGE). Notably, the existing multi-mode power managementsystem 34 may also include other types of power amplifier circuits, suchas Wi-Fi 2.4 GHz and 5 GHz power amplifier circuits, which are omittedfor the sake of simplicity.

The existing multi-mode power management system 34 includes firsttracker circuitry 52, second tracker circuitry 54, control circuitry 56,and switching circuitry 58. The switching circuitry 58 includes aplurality of first switches S₁₁-S₁₃ and a plurality of second switchesS₂₁-S₂₃. The first tracker circuitry 52 is configured to receive a firstsupply voltage V_(SUP1) at a first supply voltage input 60 and generatea first voltage V₁ at a first voltage output 62 based on the firstsupply voltage V_(SUP1). The first tracker circuitry 52 may receive thefirst supply voltage V_(SUP1) from an internal voltage source, such as alow dropout regulator (LDO), or from the second tracker circuitry 54,which can provide a higher voltage than the internal voltage source. Toprovide the first supply voltage V_(SUP1) to the first tracker circuitry52 from the internal voltage source, a first input switch S_(IN1) isclosed, while the second switch S₂₁ is open. In contrast, to provide thefirst supply voltage V_(SUP1) to the first tracker circuitry 52 from thesecond tracker circuitry 54, the second switch S₂₁ is closed, while thefirst input switch S_(IN1) is open.

The second tracker circuitry 54 is configured to receive a second supplyvoltage V_(SUP2) at a second supply voltage input 64 and generate asecond voltage V₂ at a second voltage output 66 based on the secondsupply voltage V_(SUP2). The second tracker circuitry 54 may receive thesecond supply voltage V_(SUP2) from the internal voltage source or fromthe first tracker circuitry 52. To provide the second supply voltageV_(SUP2) to the second tracker circuitry 54 from the internal voltagesource, a second input switch S_(IN2) is closed, while the first switchS₁₁ is open. In contrast, to provide the second supply voltage V_(SUP2)to the second tracker circuitry 54 from the first tracker circuitry 52,the first switch S₁₁ is closed, while the second input switch S_(IN2) isopen.

The first tracker circuitry 52 can generate the first voltage V₁ as afirst envelope tracking (ET) modulated voltage V_(ET1) in response toreceiving a first ET modulation signal 68E or generate the first voltageV₁ as a first average power tracking (APT) modulated voltage V_(APT1) inresponse to receiving a first APT modulation signal 68A. The secondtracker circuitry 54 can generate the second voltage V₂ as a second ETmodulated voltage V_(ET2) in response to receiving a second ETmodulation signal 70E or generate the second voltage V₂ as a second APTmodulated voltage V_(APT2) in response to receiving a second APTmodulation signal 70A.

The first switches S₁₁-S₁₃ and the second switches S₂₁-S₂₃ areconfigured to selectively couple the first voltage output 62 and/or thesecond voltage output 66 to provide a bias voltage(s) to one or morepower amplifier circuits among the LB power amplifier circuit 36, thefirst MB power amplifier circuit 38, the first HB power amplifiercircuit 40, the UHB power amplifier circuit 42, the second MB poweramplifier circuit 44, the second HB power amplifier circuit 46, the 2GLB power amplifier circuit 48, and the 2G HB power amplifier circuit 50.The control circuitry 56 controls the first switches S₁₁-S₁₃ and thesecond switches S₂₁-S₂₃ to support various 2G, 3G, and/or 4G operationmodes.

In one example, the existing multi-mode power management system 34 canconfigure a selected power amplifier circuit among the LB poweramplifier circuit 36, the first MB power amplifier circuit 38, the firstHB power amplifier circuit 40, the UHB power amplifier circuit 42, thesecond MB power amplifier circuit 44, and the second HB power amplifiercircuit 46 to support a 3G/4G ET single transmit (ET-STX) modeoperation, such as a WCDMA ET-STX mode operation and/or an LTE ET-STXmode operation. For example, to configure the second tracker circuitry54 and the first MB power amplifier circuit 38 in the 3G/4G ET-STX modeoperation, the control circuitry 56 provides the second ET modulationsignal 70E to the second tracker circuitry 54 and configures the firsttracker circuitry 52 to output the second voltage V₂ as the second ETmodulated voltage V_(ET2) at the second voltage output 66. The controlcircuitry 56 further configures the first tracker circuitry 52 togenerate the first voltage V₁ as the first APT modulated voltageV_(APT1) at the first voltage output 62. Accordingly, the controlcircuitry 56 opens the second switch S₂₁ and closes the first inputswitch S_(IN1) to provide the first supply voltage V_(SUP1) to the firsttracker circuitry 52 from the internal voltage source. In addition, thecontrol circuitry 56 opens the second input switch S_(IN2) and closesthe first switch S₁₁ to provide the second supply voltage V_(SUP2) tothe second tracker circuitry 54 from the first tracker circuitry 52. Assuch, the first MB power amplifier circuit 38 can amplify a 3G signal(e.g., WCDMA signal) or a 4G signal (e.g., LTE signal) based on the ETmodulated voltage V_(ET1) for transmission in the 3G/4G ET-STX mode. Itshould be appreciated that it is also possible to configure the firsttracker circuitry 52 and the first MB power amplifier circuit 38 in the3G/4G ET-STX mode operation by adding switches and/or changing switchlayout in the switching circuitry 58.

In another example, the existing multi-mode power management system 34can configure a selected power amplifier circuit among the LB poweramplifier circuit 36, the first MB power amplifier circuit 38, the firstHB power amplifier circuit 40, the UHB power amplifier circuit 42, thesecond MB power amplifier circuit 44, and the second HB power amplifiercircuit 46 to support a 3G/4G APT single transmit (APT-STX) modeoperation. For example, to configure the second tracker circuitry 54 andthe first MB power amplifier circuit 38 in the 3G/4G APT-STX modeoperation, the control circuitry 56 provides the second APT modulationsignal 70A to the second tracker circuitry 54 and configures the secondtracker circuitry 54 to output the second voltage V₂ as the second APTmodulated voltage V_(APT2) at the second voltage output 66. The controlcircuitry 56 turns off the first tracker circuitry 52. Accordingly, thecontrol circuitry 56 opens the first switch S₁₁ and closes the secondinput switch S_(IN2) to provide the second supply voltage V_(SUP2) tothe second tracker circuitry 54 from the internal voltage source. Assuch, the first MB power amplifier circuit 38 can amplify a 3G signal(e.g., WCDMA signal) or a 4G signal (e.g., LTE signal) based on the APTmodulated voltage V_(APT2) for transmission in the 3G/4G APT-STX mode.It should be appreciated that it is also possible to configure the firsttracker circuitry 52 and the first MB power amplifier circuit 38 in the3G/4G APT-STX mode operation by adding switches and/or changing switchlayout in the switching circuitry 58.

In another example, the existing multi-mode power management system 34can configure two selected power amplifier circuits among the LB poweramplifier circuit 36, the first MB power amplifier circuit 38, the firstHB power amplifier circuit 40, the UHB power amplifier circuit 42, thesecond MB power amplifier circuit 44, and the second HB power amplifiercircuit 46 to support a 3G/4G ET dual transmit (ET-DTX) mode operation,such as a WCDMA ET-DTX mode operation and/or an LTE ET-DTX modeoperation. For example, to configure the first tracker circuitry 52, thesecond tracker circuitry 54, the first MB power amplifier circuit 38,and the second HB power amplifier circuit 46 in the 3G/4G ET-DTX modeoperation, the control circuitry 56 provides the first ET modulationsignal 68E and the second ET modulation signal 70E to the first trackercircuitry 52 and the second tracker circuitry 54, respectively. Thecontrol circuitry 56 couples the first voltage output 62 of the firsttracker circuitry 52 to the second HB power amplifier circuit 46 byclosing the first switch S₁₂. As such, the second HB power amplifiercircuit 46 can amplify a 3G signal (e.g., WCDMA signal) or a 4G signal(e.g., LTE signal) based on the ET modulated voltage V_(ET1) fortransmission in the HB, while the first MB power amplifier circuit 38amplifying the 3G signal (e.g., WCDMA signal) or the 4G (e.g., LTEsignal) based on the ET modulated voltage V_(ET2) for transmission inthe MB.

The existing multi-mode power management system 34 may be furtherconfigured to support other operation modes, such as 2G-STX mode and2G-DTX mode by selectively coupling the first tracker circuitry 52and/or the second tracker circuitry 54 via the switching circuitry 58.Notably, the switching circuitry 58 is provided herein merely as anon-limiting example and should not be interpreted as being limiting. Inother words, the switching circuitry 58 can be constructed based on anynumber, type, and layout of switches.

Each of the LB power amplifier circuit 36, the first MB power amplifiercircuit 38, the first HB power amplifier circuit 40, the UHB poweramplifier circuit 42, the second MB power amplifier circuit 44, thesecond HB power amplifier circuit 46, the 2G LB power amplifier circuit48, and the 2G HB power amplifier circuit 50 may be configured toinclude at least one serial power amplifier circuit as discussed next inFIG. 2B.

FIG. 2B is a schematic diagram of an exemplary serial power amplifiercircuit 72 that can be provided in the existing multi-mode powermanagement system 34 of FIG. 2A for amplifying 2G, 3G, and/or 4Gsignals. The serial power amplifier circuit 72 includes a driver stagepower amplifier 74 and an output stage power amplifier 76 connected intendon. The driver stage power amplifier 74 is configured to amplify asignal 78 (e.g., WCDMA signal, LTE signal, etc.) to generate a driverstage signal 80. The output stage power amplifier 76 is configured tofurther amplify the driver stage signal 80 to generate an output signal82 (e.g., WCDMA signal, LTE signal, etc.). The driver stage poweramplifier 74 and the output stage power amplifier 76 are configured tooperate based on bias voltages V_(B1) and V_(B2), respectively. The biasvoltages V_(B1) and V_(B2) may be provided by the first trackercircuitry 52 and/or the second tracker circuitry 54 of FIG. 2A.

The existing multi-mode power management system 34 of FIG. 2A can beadapted to create a new multi-mode power management system forsupporting a 5G-NR power amplifier circuit(s) in various 5G-NR operationmodes. As further discussed below, the 5G-NR power amplifier circuit(s)can be supported by the first tracker circuitry 52 and the secondtracker circuitry 54. As such, it is possible to incorporate the 5G-NRpower amplifier circuit into the existing multi-mode power managementsystem 34 with minimum hardware additions, thus help to reduce componentcount, cost, and footprint of the new multi-mode power managementsystem. In addition, the new multi-mode power management system canstill support all the power amplifier circuits (2G/3G/4G) inLB/MB/HB/UHB as described above in FIGS. 2A and 2B. As such, the newmulti-mode power management system is backward compatible with theexisting multi-mode power management system 34.

In this regard, FIG. 3 is a schematic diagram of an exemplary multi-modepower management system 84, which is adapted from the existingmulti-mode power management system 34 of FIG. 2A, for supporting various5G-NR operation modes. Common elements between FIGS. 2A and 3 are showntherein with common element numbers and will not be re-described herein.In the examples discussed herein, the term 5G-NR refers to a wirelesscommunication technology defined by the third-generation partnershipproject (3GPP) in LTE Release 15 (Rel-15) and beyond.

The multi-mode power management system 84 includes a power amplifiercircuit 86 configured to amplify a 5G-NR signal 88 to an output powerlevel P_(OUT) for transmission in a 5G-NR band. In a non-limitingexample, the power amplifier circuit 86 is a Doherty-like poweramplifier circuit including a carrier amplifier 90, a peaking amplifier92, a splitter 94, and a combiner 96.

The splitter 94 splits the 5G-NR signal 88 into a first signal 98 and asecond signal 100. The first signal 98 has a first phase θ₁′. The secondsignal 100 has a second phase θ₂′, which is a 90° offset from the firstphase θ₁′. The carrier amplifier 90 is configured to amplify the firstsignal 98 to a first power level P₁ in response to receiving a firstbias voltage V_(B1) at a first bias voltage input 102. The peakingamplifier 92 is configured to amplify the second signal 100 to a secondpower level P₂ in response to receiving a second bias voltage V_(B2) ata second bias voltage input 104. The combiner 96 combines the firstsignal 98 and the second signal 100 to generate the 5G-NR signal 88 atthe output power level P_(OUT), which equals a sum of the first powerlevel P₁ and the second power levelP ₂(P _(OUT) =P ₁ +P ₂).

The multi-mode power management system 84 reuses the first trackercircuitry 52 and the second tracker circuitry 54 from the existingmulti-mode power management system 34. The first tracker circuitry 52and the second tracker circuitry 54 generate the first voltage V₁ at thefirst voltage output 62 and the second voltage V₂ at the second voltageoutput 66, respectively. The multi-mode power management system 84includes switching circuitry 106. In a non-limiting example, theswitching circuitry 106 includes a plurality of first switches S₁₁-S₁₃and a plurality of second switches S₂₁-S₂₅. Among the switches in theswitching circuitry 106, the first switches S₁₁-S₁₃ are equivalent tothe first switches S₁₁-S₁₃ in the switching circuitry 58 and the secondswitches S₂₁-S₂₃ are equivalent to the second switches S₂₁-S₂₃ in theswitching circuitry 58. Notably, the switching circuitry 106 is providedherein merely as a non-limiting example and should not be interpreted asbeing limiting. In other words, the switching circuitry 106 can beconstructed based on any number, type, and layout of switches.

The power amplifier circuit 86 may be configured to support a 5G-NR lowpower mode operation and a 5G-NR high power mode operation. In examplesdiscussed herein, control circuitry 107 may determine whether to operatethe multi-mode power management system 84 in the 5G-NR low power mode orthe 5G-NR high power mode based on a power threshold. In onenon-limiting example, if the output power level of the 5G-NR signal 88is less than or equal to the power threshold, the multi-mode powermanagement system 84 operates in the 5G-NR low power mode. Otherwise,the multi-mode power management system 84 operates in the 5G-NR highpower mode. In another non-limiting example, if peak-to-average ratio(PAR) of the output power level of the 5G-NR signal 88 is less than orequal to the power threshold, the multi-mode power management system 84operates in the 5G-NR low power mode. Otherwise, the multi-mode powermanagement system 84 operates in the 5G-NR high power mode.

In the 5G-NR low power mode, the control circuitry 107 can selectivelycouple one of the first voltage output 62 and the second voltage output66 to the power amplifier circuit 86 for providing the first biasvoltage V_(B1) and the second bias voltage V_(B2) to the carrieramplifier 90 and the peaking amplifier 92. For example, in the 5G-NR lowpower mode, the control circuitry 107 provides the first APT modulationsignal 68A to the first tracker circuitry 52 to generate the firstoutput voltage V₁ as the first APT modulated voltage V_(APT1). Thecontrol circuitry 107 can close the switch S₁₂ to couple the firstvoltage output 62 of the first tracker circuitry 52 to the first biasvoltage input 102 of the carrier amplifier 90. In addition, the controlcircuitry 107 also closes the switch S₂₄ to couple the first voltageoutput 62 to the second bias voltage input 104 of the peaking amplifier92. Accordingly, the first tracker circuitry 52 is providing the firstbias voltage V_(B1) and the second bias voltage V_(B2) to the carrieramplifier 90 and the peaking amplifier 92, respectively.

Continuing with the example above, since the first tracker circuitry 52is supplying both the first bias voltage V_(B1) and the second biasvoltage V_(B2), the second tracker circuitry 54 is freed up to supportother power amplifier circuits in the multi-mode power management system84. In this regard, the second tracker circuitry 54 can be configured toconcurrently support another power amplifier circuit in the multi-modepower management system 84. In one example, the second tracker circuitry54 can be configured to generate the second voltage V₂ as the second APTmodulated voltage V_(APT2). The control circuitry 107 may couple thesecond voltage output 66 of the second tracker circuitry 54 to a LTEpower amplifier circuit (e.g., the first MB power amplifier circuit 38)for amplifying an LTE signal. Alternatively, the control circuitry 107may couple the second voltage output 66 of the second tracker circuitry54 to a WCDMA power amplifier circuit (e.g., the second MB poweramplifier circuit 44) for amplifying a WCDMA signal.

In the 5G-NR high power mode, the control circuitry 107 couples thefirst voltage output 62 of the first tracker circuitry 52 and the secondvoltage output 66 of the second tracker circuitry 54 to the first biasvoltage input 102 of the carrier amplifier 90 and the second biasvoltage input 104 of the peaking amplifier 92, respectively. Forexample, in the 5G-NR high power mode, the control circuitry 107provides the first APT modulation signal 68A to the first trackercircuitry 52 to generate the first output voltage V₁ as the first APTmodulated voltage V_(APT1). The control circuitry 107 also provides thesecond APT modulation signal 70A to the second tracker circuitry 54 togenerate the second output voltage V₂ as the second APT modulatedvoltage V_(APT2). The control circuitry 107 can close the switch S₁₂ tocouple the first voltage output 62 of the first tracker circuitry 52 tothe first bias voltage input 102 of the carrier amplifier 90. Thecontrol circuitry 107 also closes the switch S₂₃ and the switch S₂₅ tocouple the second voltage output 66 to the second bias voltage input 104of the peaking amplifier 92.

The multi-mode power management system 84 is configured to be backwardcompatible with the existing multi-mode power management system 34 interms of supporting the 2G, 3G, and 4G power amplifier circuits invarious operation modes. In this regard, the multi-mode power managementsystem 84 can support the 3G/4G ET-STX mode, the 3G/4G APT-STX mode, the3G/4G ET-DTX mode, and the 3G/4G APT DTX mode as previously discussed inreference to FIG. 2A.

In a non-limiting example, the power amplifier circuit 86 can beprovided as a reconfigurable load modulation power amplifier circuit, asdiscussed next in FIG. 4. In this regard, FIG. 4 is a schematic diagramof an exemplary reconfigurable load modulation power amplifier circuit108 that may be provided in the multi-mode power management system 84 ofFIG. 3 for supporting the various 5G-NR operations. Common elementsbetween FIGS. 3 and 4 are shown therein with common element numbers andwill not be re-described herein.

The reconfigurable load modulation power amplifier circuit 108 includesan input impedance tuning network 110 coupled between the splitter 94and a ground. The reconfigurable load modulation power amplifier circuit108 also includes an output impedance tuning network 112 coupled betweenthe combiner 96 and the ground. The input impedance tuning network 110and the output impedance tuning network 112 are continuously controlledby a control signal 114. As such, impedance at an isolation part of thesplitter 94 and the combiner 96 is tunable such that at least one of thecarrier amplifier 90 and the peaking amplifier 92 is presented with aquadrature load impedance that ranges from around about half an outputload termination impedance to around about twice the output loadtermination impedance. For more details about the reconfigurable loadmodulation power amplifier circuit 108, please refer to U.S. patentapplication Ser. No. 14/501,453, now U.S. Pat. No. 9,484,865, issued onNov. 1, 2016, titled “RECONFIGURABLE LOAD MODULATION AMPLIFIER.”

The reconfigurable load modulation power amplifier circuit 108 can beincorporated into the multi-mode power management system 84 of FIG. 3.In this regard, FIG. 5 is a schematic diagram of an exemplary multi-modepower management system 116 incorporating the reconfigurable loadmodulation power amplifier circuit 108 of FIG. 4. Common elementsbetween FIGS. 3, 4, and 5 are shown therein with common element numbersand will not be re-described herein.

Notably, the difference between the multi-mode power management system116 and the multi-mode power management system 84 of FIG. 3 is that thereconfigurable load modulation power amplifier circuit 108 of FIG. 4 isprovided in place of the power amplifier circuit 86 of FIG. 3. As such,the multi-mode power management system 116 is compatible with themulti-mode power management system 84 of FIG. 3. Accordingly, themulti-mode power management system 116 can support all the operationmodes as described in FIG. 3. In a non-limiting example, the inputimpedance tuning network 110 and the output impedance tuning network 112can be controlled continuously by the first ET modulation signal 68E andthe second ET modulation signal 70E, respectively.

Those skilled in the art will recognize improvements and modificationsto the preferred embodiments of the present disclosure. All suchimprovements and modifications are considered within the scope of theconcepts disclosed herein and the claims that follow.

What is claimed is:
 1. A multi-mode power management system comprising:a power amplifier circuit configured to amplify a fifth-generation newradio (5G-NR) signal to an output power level for transmission in a5G-NR band, the power amplifier circuit comprising: a carrier amplifierconfigured to amplify the 5G-NR signal to a first power level inresponse to receiving a first bias voltage at a first bias voltageinput; and a peaking amplifier configured to amplify the 5G-NR signal toa second power level in response to receiving a second bias voltage at asecond bias voltage input; wherein a sum of the first power level andthe second power level equals the output power level; first trackercircuitry configured to generate a first voltage at a first voltageoutput; second tracker circuitry configured to generate a second voltageat a second voltage output; and control circuitry configured to: couplethe first voltage output to the first bias voltage input and the secondbias voltage input in a 5G-NR low power mode; and couple the firstvoltage output and the second voltage output to the first bias voltageinput and the second bias voltage input, respectively, in a 5G-NR highpower mode.
 2. The multi-mode power management system of claim 1 whereinthe control circuitry is further configured to: operate in the 5G-NR lowpower mode in response to the output power level of the 5G-NR signalbeing less than or equal to a power threshold; and operate in the 5G-NRhigh power mode in response to the output power level of the 5G-NRsignal being greater than the power threshold.
 3. The multi-mode powermanagement system of claim 1 further comprising switching circuitry,wherein the control circuitry is further configured to control theswitching circuitry to: couple the first voltage output to the firstbias voltage input and the second bias voltage input in the 5G-NR lowpower mode; and couple the first voltage output and the second voltageoutput to the first bias voltage input and the second bias voltageinput, respectively, in the 5G-NR high power mode.
 4. The multi-modepower management system of claim 1 wherein: the first tracker circuitryis further configured to: generate the first voltage as a first envelopetracking (ET) modulated voltage based on a first supply voltage receivedat a first supply voltage input in response to receiving a first ETmodulation signal; and generate the first voltage as a first averagepower tracking (APT) modulated voltage in response to receiving a firstAPT modulation signal; and the second tracker circuitry is furtherconfigured to: generate the second voltage as a second ET modulatedvoltage based on a second supply voltage received at a second supplyvoltage input in response to receiving a second ET modulation signal;and generate the second voltage as a second APT modulated voltage inresponse to receiving a second APT modulation signal.
 5. The multi-modepower management system of claim 4 wherein: the first tracker circuitryis further configured to generate the first voltage as the first APTmodulated voltage in the 5G-NR low power mode and the 5G-NR high powermode; and the second tracker circuitry is further configured to generatethe second voltage as the second APT modulated voltage in the 5G-NR highpower mode.
 6. The multi-mode power management system of claim 4 whereinthe power amplifier circuit further comprises: a splitter configured tosplit the 5G-NR signal into a first signal of a first phase and a secondsignal of a second phase having a ninety-degree offset from the firstphase; the carrier amplifier further configured to amplify the firstsignal to the first power level in response to receiving the first biasvoltage at the first bias voltage input; the peaking amplifier furtherconfigured to amplify the second signal to the second power level inresponse to receiving the second bias voltage at the second bias voltageinput; and a combiner configured to combine the first signal at thefirst power level and the second signal at the second power level togenerate the 5G-NR signal at the output power level.
 7. The multi-modepower management system of claim 6 wherein the power amplifier circuitfurther comprises an input impedance tuning network coupled to thesplitter and an output impedance tuning network coupled to the combiner.8. The multi-mode power management system of claim 7 wherein the controlcircuitry is further configured to control the input impedance tuningnetwork and the output impedance tuning network via the first ETmodulation signal and the second ET modulation signal, respectively. 9.The multi-mode power management system of claim 4 further comprising along-term evolution (LTE) power amplifier circuit configured to amplifyan LTE signal for transmission in an LTE band.
 10. The multi-mode powermanagement system of claim 9 wherein the control circuitry is furtherconfigured to couple the second voltage output to the LTE poweramplifier circuit for amplifying the LTE signal in the 5G-NR low powermode.
 11. The multi-mode power management system of claim 9 wherein thecontrol circuitry is further configured to couple the first voltageoutput to provide the first voltage as the first APT modulated voltageto the LTE power amplifier circuit and turn off the second trackercircuitry in an LTE ET single transmit mode.
 12. The multi-mode powermanagement system of claim 9 wherein in an LTE ET single transmit mode,the control circuitry is further configured to: couple the first voltageoutput to the LTE power amplifier circuit to provide the first voltageto the LTE power amplifier circuit as the first ET modulated voltage;and couple the second voltage output to the first supply voltage inputto provide the second voltage as the second APT modulated voltage to thefirst tracker circuitry.
 13. The multi-mode power management system ofclaim 9 further comprising a second LTE power amplifier circuitconfigured to amplify the LTE signal for transmission in a second LTEband, wherein the control circuitry is further configured to couple thefirst voltage output and the second voltage output to the LTE poweramplifier circuit and the second LTE power amplifier circuit,respectively, in an LTE dual transmit mode.
 14. The multi-mode powermanagement system of claim 4 further comprising a wideband code divisionmultiple access (WCDMA) power amplifier circuit configured to amplify aWCDMA signal for transmission in a WCDMA band.
 15. The multi-mode powermanagement system of claim 14 wherein the control circuitry is furtherconfigured to couple the second voltage output to the WCDMA poweramplifier circuit for amplifying the WCDMA signal in the 5G-NR low powermode.
 16. The multi-mode power management system of claim 14 wherein thecontrol circuitry is further configured to couple the first voltageoutput to provide the first voltage as the first APT modulated voltageto the WCDMA power amplifier circuit and turn off the second trackercircuitry in a WCDMA ET single transmit mode.
 17. The multi-mode powermanagement system of claim 14 wherein in a WCDMA ET single transmitmode, the control circuitry is further configured to: couple the firstvoltage output to the WCDMA power amplifier circuit to provide the firstvoltage to the WCDMA power amplifier circuit as the first ET modulatedvoltage; and couple the second voltage output to the first supplyvoltage input to provide the second voltage as the second APT modulatedvoltage to the first tracker circuitry.
 18. The multi-mode powermanagement system of claim 14 further comprising a second WCDMA poweramplifier circuit configured to amplify the WCDMA signal fortransmission in a second WCDMA band, wherein the control circuitry isfurther configured to couple the first voltage output and the secondvoltage output to the WCDMA power amplifier circuit and the second WCDMApower amplifier circuit, respectively, in a WCDMA dual transmit mode.19. A multi-mode power management system comprising: a power amplifiercircuit configured to amplify a signal to an output power level, thepower amplifier circuit comprising: a carrier amplifier configured toamplify the signal to a first power level in response to receiving afirst bias voltage at a first bias voltage input; and a peakingamplifier configured to amplify the signal to a second power level inresponse to receiving a second bias voltage at a second bias voltageinput; wherein a sum of the first power level and the second power levelequals the output power level; first tracker circuitry configured togenerate a first voltage at a first voltage output; second trackercircuitry configured to generate a second voltage at a second voltageoutput; and control circuitry configured to: couple the first voltageoutput to the first bias voltage input and the second bias voltage inputin a low power mode; and couple the first voltage output and the secondvoltage output to the first bias voltage input and the second biasvoltage input, respectively, in a high power mode.
 20. The multi-modepower management system of claim 19 further comprising at least oneserial power amplifier circuit, the at least one serial power amplifiercircuit comprising: a driver stage power amplifier configured to receivea second signal and amplify the second signal to generate a driver stagesignal; and an output stage power amplifier configured to amplify thedriver stage signal to generate a second output signal.
 21. Themulti-mode power management system of claim 20 wherein: the firsttracker circuitry is further configured to: generate the first voltageas a first envelope tracking (ET) modulated voltage based on a firstsupply voltage received at a first supply voltage input in response toreceiving a first ET modulation signal; and generate the first voltageas a first average power tracking (APT) modulated voltage in response toreceiving a first APT modulation signal; and the second trackercircuitry is further configured to: generate the second voltage as asecond ET modulated voltage based on a second supply voltage received ata second supply voltage input in response to receiving a second ETmodulation signal; and generate the second voltage as a second APTmodulated voltage in response to receiving a second APT modulationsignal.
 22. The multi-mode power management system of claim 21 whereinthe control circuitry is further configured to selectively couple one ormore of the first voltage output and the second voltage output to the atleast one serial power amplifier circuit.